Indium rod.
This is very, very high purity indium, and the surface texture comes not from bending (as one might do to hear the crackling sound it makes) but rather from etching to show the crystal structure.Source:Juan JimenezContributor:Juan JimenezAcquired:2 December, 2007Text Updated:7 December, 2007Price: DonatedSize: 2.5"Purity: 99.99999%